The results of this study suggest that TS and NTS performance during crisis management in an intraoperative simulated scenario are related. Specifically, residents who demonstrated good performance for one domain (TS or NTS) tended to show similar levels of performance for the other. The opposite was also true, poor performance for one domain (TS or NTS) was often accompanied by poor performance for the other. From our results, performance in one domain explains as much as 23% of the variance of the other.
Our study supports findings of other research. McCulloch and colleagues19
investigated the influence of NTS on surgical outcomes and technical performance. Their results showed an improvement of TS performance through NTS training by reducing procedural errors. Most notably, improving situation awareness led to a reduced procedural error rate. Another study, involving teams during elective laparoscopic cholecystectomies, demonstrated that technical errors were negatively correlated with the surgeons' situational awareness scores.21
Similar to our findings, both studies demonstrate a relationship between TS and NTS. Other studies have assessed TS and NTS during simulated surgical procedures, but did not investigate the relationship between the different types of skills.6,9,17,20
While previous research used elective and non-urgent surgical situations, or focused on the performance of the surgeon, our study adds to the previous literature by specifically exploring the relationship between TS and NTS during crisis situations in anaesthesia.
Cognitive load theory may provide an explanation for the relationship observed between TS and NTS. Sweller27
describes cognitive load theory as a model of human cognitive architecture made up of a limited capacity working memory system and unlimited long-term memory. This theory has been developed substantially since its first delineation and has since been applied to the field of medical education.28–30
A recent review by van Merriënboer and Sweller30
provides an overview of design and strategies related to cognitive load theory in healthcare professional education. While long-term memory has unlimited capacity, working memory can only process a limited amount of novel information at any one time.30,31
Strategies are often implemented to effectively accommodate the limited capacity system of working memory. The development of expertise includes the use of schemas, developed from learned previous education, experiences, and/or tasks. Ideally, these schemas are developed in practice, and then serve as effort reduction strategies aimed at aligning task demands with working memory capacities. This may then reduce cognitive load and create ‘space’ for additional cognitive demands.
The case used in this study (intraoperative cardiac arrest) is a volatile situation with high cognitive load due to the number of cognitive processes that need to take place, the number of behaviours that need to be demonstrated, the challenges of multitasking, and the constraint of time. Pre-existing automated schemas (or expertise) in one domain (i.e. TS) may have reduced individual cognitive load, thereby freeing cognitive resources for the other domain (i.e. NTS). This could explain why participants with good TS demonstrated better non-technical performance and vice versa.
Access to long-term memory schemas developed from earlier experiences lowers cognitive load for working memory, and therefore allows for greater mental resources for new incoming information. The working memory of a resident can be affected by the intrinsic nature of the task (e.g. intraoperative cardiac arrest). The number of task elements (i.e. incoming information) must be coordinated in working memory to result in a successful performance. Therefore, a resident who managed the scenario in possession of good TS in advanced cardiac life support (i.e. knowledge of course of action, handling of defibrillator, options of medication) may have required fewer mental resources, freeing some of the working memory for non-technical elements. The quantity of individual ‘chunks’ residents can simultaneously manage may depend on the individual level of expertise for a particular problem. This is consistent with the literature, which suggests expertise may have an effect on cognitive load due to an improved ability to retrieve information from long-term memory more rapidly.32
This study has several limitations. First, the skills were assessed during a specific anaesthesia cardiac arrest scenario. Although it has been shown that NTS seem to be transferable between acute crisis management scenarios, this might not be the case for TS, and therefore, the results may not be generalizable to other populations or situations.33
Despite the well-structured and algorithm-driven scenario used in this study, it is possible that not all NTS can be assessed during a short scenario.
Secondly, the checklist might not have been able to purely capture TS, and instead, might have measured behavioural aspects. We have tried to limit any bias by recruiting independent raters for rating TS and NTS: the two raters who used the ANTS were different from the two who had used the TS checklist. However, the ‘call for help’ item is present in both the Checklist and in the ANTS scale, therefore, potentially creating a bias in the results.
Finally, the nature of the relationship between TS and NTS was beyond the scope of this study. The aim of the study was to explore the broad link between performance entities expressed by TS and NTS, using the correlation between both. Therefore, further studies investigating the direction of association and nature of the relationship between TS and NTS are needed.